Eyeglass frame adapted for the removal and insertion of lenses

Abstract

This invention provides for making a cam arm with a wave-shaped or curved portion adapted to fit within a recess on the top of the upper closure block of the frame so that the frame eyewire is securely closed in place.

1. An eyeglass frame having lenses and a lower eyewire closure block and an upper eyewire closure block comprising
 a cam mechanism including a cam lock formed of a pair of cam heads connected to an arm of said cam lock, a hinge pin extending through a hole in a closure block of said frame, 
 said pair of cam heads being pivotally connected to said hinge pin and to said lower eyewire closure block by a pivot point so that when said cam arm is moved in a first direction to a first position, said cam heads rotate away from said lower eyewire closure block and cause said lower eyewire closure block and said upper eyewire closure block to separate a distance thereby opening said frame eyewire for a lens to be removed, inserted or replaced; and said arm being moved to a second position opposite said first position which cause said cam heads to rotate back into engagement against said lower eyewire closure block thereby causing said lower eyewire closure block to come together with said upper eyewire closure block and said frame to close, the improvement comprising: 
 said cam arm including a rounded or wave-shaped portion adapted to be fitted on top of or within a recess in said upper eyewire closure block of said frame to provide for a more secure closure of said frame while making allowance for said lenses being slightly over cut and to prevent accidental opening of said frame. 
 
   
   
     2. The frame according to  claim 1  wherein said cam arm is made from a suitable elastic material to enable said frame to lock securely even if said lens is over-cut and to provide clamping force to keep the upper and lower eyewire closure blocks pressed together. 
   
   
     3. The frame according to  claim 2  wherein said suitable elastic material is spring steel. 
   
   
     4. The frame according to  claim 1  wherein said frame further includes a non-threaded hinge pin to insure proper alignment of said cam arm and a groove cut into said upper and lower eyewire closure blocks.